STEP diagram

FIGURE 6.7. STEP Diagram for the Spanish Campsite Disaster (page 1). 

This stage involved the identification of critical actions and events in the incident process. Three critical events were identified from the STEP diagram. These were... 

FIGURE 7 2 STEP Diagram of Hydrocarbon Leak from Pipe, Page 1 of 4. 

Fig. 31.12. Dance-step diagram, illustrating a cycle of the iterative NIPALS algorithm. Step 1 multiplies the score vector t with the data table X, which produces the weight veetor w. Step 2 normalizes w to unit sum of squares. In step 3, X is multiplied by w, yielding an updated t.

Each step signifies a milestone in the sample s travel through the laboratory. Unlike other seven-step diagrams with irreversible flow that we have seen in previous chapters, a unique feature of laboratory process is that the relationships between individual steps are for the most part reversible. This means that there is a viable chance to correct an error made at the previous step. This reversibility is the greatest advantage of the laboratory process. As laboratories handle thousands of samples and analyze them by dozens of various methods, the possibility for making an error at any step is real, but so is the opportunity to correct the error. Obviously, some errors... 

The first member in (23) gives the irreducible part of step diagram Fig.2a, the second determines its reducible part. The third member and the quadratic member in (18) cancel each other. 

Explain this using the energy step diagram in Figure 4. 

Step diagram of the distillation of a crude fatty acid mixture... 

Both groups created STEP diagrams that gave a coherent accormt of the incident from the time of the weather forecast rmtil the heaves declined. The diagram created... 

Figure 1. Scenario analysis (STEP-diagram)-group 1.

The step-by-step diagram of how a reaction works is known as its mechanism. 

The situation was analysed by the STEP investigation method (Sequentially Timed Events Plotting, see Hendrick Benner, 1987). The STEP diagram is shown in Figure 1. 

The following safety problems (triangles in the STEP diagram) were obtained during the analysis ... 

Step-2 Mapping of events The STEP-diagram method (Passmore, 1988) was used to map the work processes involved in the experienced incidents/events. Figure 2 illustrates an extract of such a mapping for the Line recovery phase at the field. Activities in the main work process are linked with solid lines in Figure 2, whereas actors indirectly involved are linked with dashed vertical lines to the core activities. The actors involved in rig move operations are specified to the left in the STEP diagram. 

Figure 2. Extract of a STEP diagram Line recovery.

Step-4 Identification of barriers Barrier identification and analyses were conducted in a Workshop (WS) with marine experts from Statoil and partners. Results from the WS were documented in the prepared STEP diagrams, preliminary Bow-tie diagrams and work sheets for further analysis. Only scenarios with end consequences implying a major accident potential were focused. 

The analysis of historical events and the preparation of STEP diagrams, bow-ties and work sheets were done in forehand. Although the approach as a whole has not been applied earlier, well defined methods were combined to form the whole methodology both during the preparation phase and accomplishment of the WS. A natural part of the process was thus to adjust the approach continuously based on findings and experiences, as well as feedback from the customer throughout the process. 

The review of historical incidents and events, along with mapping in STEP diagrams gave a good basis for the scenario identification. However, other approaches may also apply to this step as discussed in the previous section. Additionally, the bow-tie method for scenario analysis was valuable in sense of providing fruitful WS discussions. It also provided a good platform for the barrier evaluations and visualization of the main results. 

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